It's not even worth trying Lowe's. Home Depot and Lowes are worthless for any hardware other than standard hex stuff. Do you have a better place in town? Ace may have options. Luckily my local place, "Supply Hardware" has rows and rows of hardware bins. I'd be SOL without that place.
I actually have a fastener warehouse about 20 miles from me. All of the local small stores mostly stock metric, and nothing under 1.5” so far in 1/4-20.